Means for cleansing waste lubricating oils



Oct. 10, 1933. c. E. FOX

MEANS FOR CLEANSING WASTE LUBRICATING OILS Filed May 27, 1929 Fla].

Patented Oct. 10, 1933 UNITED STATES MEANS FOR CLEANSKNG WVASTE LUBRICAT- ING OILS 7 Charles Ernest Fox, Brighton, England, assignor to British Oil Cleaners Limited, London,

England Application May 27, 1929, Serial No. 366,456, and in Great BritainJune 1, 1928 4 Claims. (01. 19616) This invention provides a simple and efiicient method and means whereby waste or dirty lubricating and other oils can be readily cleansed to render sa d oils fit for re-use.

The method of cleansing waste or dirty lubricating and other oils, according to the present invention, consists in circulating hot water through the oil to be treated in a downward direction by thermo-siphon principle, heating the oil in a slow even manner, circulating the oil by convection currents to intermix the molecules of oil with the hot water without agitation sufficient to form an emulsion, liberating the entrained air in the oil from the top surface thereof by th slow circulation of the heated oil, the circulating hot water being spread over the'top of the oil to sink by gravity therethrough to set up a slow draggng action to drive down, all the impurities which are capable of being washed out or precipitated, which impurities form a layer separating the cleaned oil from the water, all in one operat on and in one and the same apparatus.

It forms a feature of the invention that soda, acid or other cleansing chemicals is or are or may be added to the water, and also that some fine insoluble powder, such, for instance, as fullers earth, may be added to the water to assist in the precipitating of the impurities in the oil.

The means for carrying out the cleansingor washing consists of a tank, a hot water circulating member connecting the bottom part of the tank with the upper part thereof, a heater. (electric, steam, gas or oil) for heating the circulating member, and a spreader device located in the upper part of the tank for spreading the circulating hot water on to the Waste or dirty oil.

'For a ready understanding of the invention, reference is to be hadto the following descriptt'on and accompanying sheet of drawing, where- Figure 1 is a vertical sectional view illustrative of an apparatus constructedin accordance with the invention.

Figure 2 is a vertical sectional view illustrative of modifications of said apparatus.

Like numerals of reference indicate corresponding parts in said figures.

In carrying out the invention and referring first to Figure l of the drawing, 1 represents the tank in which is enclosed the water circulating pipe, the same consisting of a vertically disposed straight portion 2 with a bell-shaped lower portion 3 provided with holes or perforations 4 there in, and 5 represents an electric heater extending upwardly into the portion 2 aforesaid of the circulating pipe.

In the upper part of the tank 1 is located the sprayer or spreader 6, the same being positioned above the upper end or mouth of the tube Z and at a convenient distance from said upper end or mouth, said sprayer or spreader 6 being supported from the cover 7 ofthe tank 1 aforesaid, or attached to the upper end of the tube 2.

In use, the tank I is filled to'a level a little below the mouth of the tube 2, with oil (to be cleansed or washed) and water, and the-water is heated by the heater 5 until steam bubbles are generated. a

"The steam bubbles rise up the tube 2 and displace water over the mouth thereof, which, by striking or impinging against the sprayer or spreader 6, is thrown down and distributed in'fine streams into the oil 8. a a

The hot water sinks through the oil 8, which oil 8 circulates owing to the convection currents set up by the heated tube 2, and drives down the impurities or foreignmatter from the'oil, and at the same time the oil is heated by the water so i that entrained air therein is liberated and aids in they precipitating of the impurities or foreign matter, which form a layer 9 separating the oil 8 fromthe water 10 in the lower part of the tank 1 aforesaid. v r

The water, having sunk through'the oil, passes through the holes or perforations 4 into'the hell 3 of the tube 2 and is-re-heated'by the heater 5 to form fresh steam bubbles thereby maintaining the circulation of the water. I

When the heat is turned off, the contents of the tank are allowed to settle and cool, and, when cool, the oil is either siphoned off or drawn off by way of taps 11, the dirt and water being emptied off by way of the tap 12.

Referring now to the modified arrangement of apparatus shown in- Figure 2, the inner member 2 is formed with an inverted cone-like lower portion 3 and an inwardly and downwardly curved mouth or spreader 6.

To heat the water 10, use is made of a steam coil 13 inserted in the space obtaining between the wall of the tank 1 and the inner member 2 aforesaid.

Alternatively, the heating may be effected by means of an electric heater 6 disposed exterior of the wall of the tank 1, or by means of a gas or oil heater 14 disposed under the bottom of the tank v1 aforesaid, or it may be by means of an electric immersion heater which takes the place of the steam coil 13 aforesaid.

With the above arrangements of heating, the space between the tank 1 and the inner member 2 functions in similar manner to the tube 2 described with reference to Figure 1 aforesaid.

In use, the tank 1 is filled to a level a little below the upper end of the inner member 2 with water and the inner member with the waste or dirty oil requiring cleansing or washing, and the water is heated until steam bubbles are generated. The steam bubbles rise up in the space between the tank 1 and the inner member 2 and displace water over the mouth 6 of said inner member 2 on to the oil in said inner member.

The water sinks through the oil 8, which oil 8 circulates owing to the convection currents set up by the heated inner member 2, and drives down the impurities or foreign matter from the coil and, at the same time, the oil is heated by the water so that entrained air therein is liberated and aids in the precipitating of said -impurities or foreign matter, which form a layer 9 separating the oil 8 from the water in the lower part 3 of the inner member 2, and consequently the lower part of the tank 1 aforesaid.

By reason of the hot water being outside of the inner member or oil container 2, said hot water performs the function of a hot water jacket, thereby maintaining a more uniform temperature during the cooling off, and avoiding, whilst cooling off, convection currents inthe oil which have a tendency to keep the impurities in circulation.

Further, the tank, in both'of the above-described arrangements, is, for the purpose of ensuring slow cooling off, lagged, with any convenient non-conducting material. I

Soda, acid or other cleansing chemicals may be introduced into the water to assist in effecting a thorough washing of the oil, or a fine insoluble powder, such, for instance, as fullers earth may be introduced into the water and circulated in the form of muddy water. The fine particles of the powder'aid in driving down the impurities or foreign matter in the oil, and sink to the bottom of the tank, and, after settling, may 01f for further use. I

I claim:- i 1. Apparatus for separating foreign particles of colloidal size from used lubricating oil, comprising a vessel to contain the oil and a quantity of water to float the oil, a tube within the vessel in communication at its lower end with the vessel near the bottom thereof below the water level and also in communication at its upper end with the vessel above the oil level, and a selfcontained electric heater within said tube for causing a circulation of the water upwardly through the tube, said tube being directly ex: posed both inside and outside to the interior of the vessel whereby the oil surrounding the tube is heated by the hot water flowing upwardly through the tube, the vessel being entirely closed andvalso being entirely devoid of heating means above the oil level.

be tapped 2. Apparatus for separating foreign particles of colloidal size from used lubricating oil, comprising a vessel to contain the oiland a quantity of water to float the oil, a tube within the vessel in communication at its lower end with the vessel below the water level and also in communication at its upper end with the vessel above the oil level, and self-contained electric water heating means within said tube to cause a circulation of the water upwardly through the tube whereby the water so circulated gravitates through the oil to remove foreign particles therefrom without disturbing the equilibrium of the oil, said tube being directly exposed both inside and outside to the interior of the vessel whereby the oil surrounding the tube is heated by the hot water flowing upwardly through the tube, the vessel being entirely closed and also being entirely devoid of heating means above the oil level.

3. Apparatus for separating foreign particles of colloidal size from used lubricating oil, comprising a vessel to contain the oil and a quantity of water to float the oil, means within the vessel providing a passageway for the circulation of the water upwardly above the oil level without direct contact with the oil, and water heating means within said passageway to cause an upward circulation of the water through said passageway whereby] the water so circulated gravitates through the oil to remove foreign particles therefrom without disturbing the equilibrium of the oil,,the means providing said passageway being directly exposed in heat exchange relationship both to the upwardly-circulating water and to the oil whereby the oil is heated by the upwardly flowing hotwater, the vessel being entirely closed and also being entirely devoid of heating means above the oil level.

4. Apparatus for separating foreign particles of colloidal size from used lubricating oil, comprising a vessel to contain a quantity of water, anannular partition within said vessel spaced from the sides of the vessel and providing a chamber within the vessel to contain the oil, said chamber opening at its bottom into the vessel below the water level whereby the oil is floated on water within the chamber, said chamber opening at its top into the vessel above the oil and the water levels, and water heating means within the vesseloutwardly of said annular partition to cause an upward circulation of the water through the space between the casing sides and the partition, whereby the water so circulated overflows the upper edge of the partition and gravitates through the oil to remove foreign particles therefrom without disturbing the equilibrium of the oil, said partition being directly exposed at both its inner and its outer sides to the interior of the vessel whereby the oil contained within the chamber formed by the partition is heated by the hot water flowing upwardly through the passageway between the partition and the casing sides.

CHARLES ERNEST FOX. 

